Some scholars think that 'qilai(起来)' has finished its process of grammaticalization,while 'qiqu(起去') has not.This paper points out that serving as complements of verbs systematically is the sufficient condition for judging the grammaticalization of disyllabic directional verbs.In classical Chinese it was quite rare to find complements served by disyllabic directional verbs.But in vernacular Chinese spoken in near-present time,the system of disyllabic directional verbs has already come into being,which is quite similar to those in contempora...
